Dredger



T S I R H 0 L I G l D- DREDGER.

Patented May 13,1884.

N. FETERs. "Mu-Lithograph", Wnhlngtun. D. C.

UNTTE STATES ATENT @rrrcn.

DREDGER.

SPECIFICATION forming part of Letters Patent No. 298,573, dated May 13, 1884:. Application filed June .28, 1883 No model.)

To aZZ whom it may concern:

Be it known that I, DANIEL J. GILcHRIs'r, a citizen of the United States of America, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Dredgers and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

This invention relates to certain new and useful improvements in that class of excavating apparatus which are known technically as clamshell dredgers, its object being to provide such a dredge with means whereby the scoops or buckets may be readily opened and closed; and it consists more especially in the construction of the dredge and operating parts, as will be hereinafter fully set forth, and pointed out in the claims.

In the annexed drawings, which illustrate my invention, Figure 1 is a side view showing the buckets. closed in full lines, the same being represented open in dotted lines; and Fig. 2 an edge view with the upper part of the bucket broken away.

In the accompanying drawings, A A represent two rigid poles, which are securely attached to a cross-head, B, which cross-head is provided with side journals, b. To these journals are. pivoted the links 0 O, which are pivotally attached to about the central portions of the outer sides of the scoops by means of outwardly-proj ecting pins 1).

Vithin the cross-head B is formed an opening, a, through which passes the pole A, to which is attached means for opening and closing the buckets or dredges. The buckets or dredges D are provided on their upper inner edges with eyes 6, by means of which they are securely hinged-to the side pieces, D, of the dredge, which are also provided with corresponding eyes, through which pass transverse pintles. The side pieces, D D, are wedgeshaped, as shown in Fig. 1, and are provided at their upper corners with eyes, through which pass transverse bars or pintles, by which the same are pivotally attached to the scoops, the scoops being provided with eyes, through which the bars or pintles pass, by which connecting means the wedge-shaped portions D D are always held in a position between the scoops. In practice the wedge-shaped portions D D or side pieces will be made of metal of such a thickness and rigidity as not to bend, and when the scoops are open the side pieces will depend from the pintles and enter the material to be removed before the scoops are closed.

By the means above set forth the buckets are attached securely and movably upon said pintles, so that they may swing thereon outwardly, as shown in dotted lines in Fig. 1.

To the lower end of the pole A are secured straps E, which are parallel with each other at the point of attachment to the pole A, and to a point below the same, for the reception of a pulley or block, G, as shown. Below the pulley or block these straps diverge and extend downwardly to the hinges upon the scoops,

where they are secured thereto by means of the pintles, which pass through said hinges and perforations in the lower ends of the straps E E. At a point below the parallel portion of these straps E E is rigidly secured a downwardly-projecting wedge, F, which is provided, at a point in a'line with the hinges on the scoop, with a parallel portion, as shown in Fig. 2. these means attached to the inner upper pivoted ends of the scoop, and when the same is depressed the scoop will be thrown open or assume a position shown in dotted lines in Fig. 1.

The crane of the dredging-machine is of ordinary construction, and is provided with the usual chains for raising the scoop and poles, to which crane is secured a cross-head having suitable means-as clamps and levers-for binding or securing the poles A A A, which pass through suitable perforations thereon.

The cross-head may, if desirable, be mounted in a carriage which is movable to and fro along the horizontal arm of the crane, so that the distance of the scoop from the dredgingmachine may be regulated.

It will be seen that the pole A is by The operation of my invention is as follows: \Vhen the dredge is about to be lowered, the scoops D D should be in the position shown in dotted lines, Fig. 1, or open. The side pieces, D D, enter the earth and hold the scoop in position. The poles A A are then forced downward, so as to close the scoops, as shown in full lines, the pole A being clamped or held rigid while the poles A A are being forced downward. To open the scoops and drop the contents, the action is reversed. Under the pulley G a chain passes, which is employed to raise the pole A and the parts of the scoop attached thereto. The portion F, which is attached to the arms or bars E E, and is wedge-shaped at its lower end and pointed, as shown, serves a twofold purpose. The point of this wedge enters the ground and serves to hold the scoops against displacement when they are forced into the earth. It also assists in opening and closing the scoop.

Having thus described my invention, what I 1 claim as new, and desire to secure by Letters Patent, is-- 1. In a dredging apparatus or bucket, the scoops D D, hinged at their upper end to central wedge-shaped side pieces, D D, and connected to a movable pole, A, by straps or connections E E, and to poles A by the pivoted links 0 C, substantially as shown, and for the purpose set forth.

2. In a dredging apparatus, the poles A A A, carrying the scoops D D, having side pieces, D D, links 0 O, and wedge-shaped portion F, connecting an operating means, the parts being combined and organized substantially as shown.

In testimony whereof I affix my signature in presence of two witnesses.

DANIEL J. GILCHRIST.

WVitnesses:

A. J. KELLY, J r., J NO. W. HERRON. 

